Heinzel, A. [P:(DE-Juel1)VDB67315] ; Hautzel, H. [P:(DE-Juel1)VDB571] ; Poeppel, T. D. [P:(DE-Juel1)VDB22367] ; Boers, F. [P:(DE-Juel1)VDB131] ; Beu, M. [P:(DE-Juel1)VDB100] ; Mueller, H.-W. [P:(DE-Juel1)VDB78236]